The effect of electrodeposited porous plate on the CHF in saturated pool boiling of water

Abstract

Since boiling is a phenomenon with high heat transfer performance, it is expected to be used in various industrial fields such as emergency cooling in nuclear power plants, power device cooling for EVs and next-generation CPU cooling in data centers. So far, various research on boiling have been carried out in the background of these trends. In particular, many studies have been conducted to improve the critical heat flux (qCHF) which is the limit of boiling heat transfer. However, since the mechanism of qCHF is a complex phenomenon, the methods of qCHF improvement are still unconstructed. Here we demonstrate the high-performance heat transfer surface using electrodeposition which fabricates copper porous plate. We found that this copper porous plate has higher qCHF (3.7 MW/m2) than the plain surface (1.3 MW/m2) in saturated pool boiling of water at atmospheric pressure. The structure of copper porous plates is investigated by X-ray CT and SEM. The copper porous plates have a honeycomb porous structure consisting of porous area and vapor escape channels extending vertically from the substrate. In addition, the diameter of the vapor escape channels increases from the substrate to the top surface. This surface structure can supply the coolant to the heat transfer surface with the reduction of pressure drop. Our results show that the mechanism of qCHF improvement using porous plate depends on the wicking phenomenon and structure. We expect that these results will help in the development of high-performance heat transfer surfaces for various industrial applications.

Keywords

• pool boiling
• critical heat flux
• porous structure
• capillary force
• electrodeposition
• wickability
• honeycomb porous plate
• capillary limit model